High-Pressure Discharge Lamp with an Improved Starting Capability, as Well as a High-Voltage Pulse Generator

Abstract

A spiral pulse generator is used to start the high-pressure discharge lamp, and is accommodated directly in the outer bulb of the lamp. The spiral pulse generator uses a material with a matched ∈ and μ.

Description

TECHNICAL FIELD[0001]The invention is based on a high-pressure discharge lamp in accordance with the preamble of claim 1. Such lamps are in particular high-pressure discharge lamps for general lighting or for photo-optical purposes. The invention furthermore relates to a high-voltage pulse generator which can be used in particular for a lamp.PRIOR ART[0002]The problem of starting high-pressure discharge lamps is at present solved by virtue of the fact that the starting device is integrated in the ballast. One disadvantage with this is the fact that the feed lines need to be designed to be resistant to high voltages.[0003]In the past, repeated attempts have been made to integrate the starting unit in the lamp. These attempts involved integrating it in the base. Particularly effective starting which promises high pulses is achieved by means of so-called spiral pulse generators; see U.S. Pat. No. 3,289,015. Quite some time ago such devices were proposed for different high-pressure disc...

AI Technical Summary

Benefits of technology

[0012]The spiral pulse generator is a component which combines the properties of a capacitor with those of a waveguide for generating starting pulses with a voltage of at least 1.5 kV. For production purposes, two ceramic “green films” have a metallic conductive paste printed on them, are subsequently wound in offset fashion to form a spiral and finally pressed isostatically to form a molding. The subsequent co-sintering of metal paste and ceramic film takes place in air in the temperature range of between 800 and 900° C. This processing allows the operating range of the spiral pulse generator to include temperature loading of up to 700° C. As a result, the spiral pulse generator can be accommodated in the direct vicinity of the discharge vessel in the outer bulb, but also in the base or in the immediate vicinity of the lamp.

[0016]In addition, a spiral pulse generator can be dimensioned such that the high-voltage pulse even enables hot-restarting of the lamp. The dielectric made from ceramic is characterized by an extremely high relative permittivity ∈ of ∈>10, with it being possible for an ∈ of typically 70, up to ∈=100 to be achieved, depending on the material and construction. This allows for a very high capacitance of the spiral pulse generator and allows for a comparatively large temporal width of the pulses generated. This results in a very compact design of the spiral pulse generator being possible, so that it can be integrated in conventional outer bulbs of high-pressure discharge lamps.

[0017]The high pulse width also facilitates the flashover in the discharge volume.

Problems solved by technology

One disadvantage with this is the fact that the feed lines need to be designed to be resistant to high voltages.

However, they could not establish themselves because, for one reason, they are too expensive.

Secondly, the advantage of integrating them in the base is insufficient since the problem of supplying the high voltage into the bulb remains.

The probability of damage to the lamp, whether it be insulation problems or a rupture in the base, therefore increases considerably.

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